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Programming information – Toshiba 6F3B0253 User Manual

Page 101

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6F3B0253

Basic Hardware and Function

99

6. Programming Information

6.8 Program execution sequence

The instructions execution sequence is shown below.

(1) They are executed in the sequence from block 1 through the final block, which

contains the END instruction (or IRET in an interrupt program).

(2) They are executed in the sequence from rung 1 through the final rung in a block

(or the END instruction).

(3) They are executed according to the following rules in any one rung.

?

When there is no vertical
connection, they are
executed from left to right.

@

When there is an OR
connection, the OR logic
portion is executed first.

A

When there is a branch, they
are executed in the order from
the upper line to the lower line.

B

A combination of

@

and

A

above.

The instructions execution sequence in which function instructions are included also
follows the above rules. However, for program execution control instructions, such as
jumps (JCS), loops (FOR-NEXT), subroutines (CALL-SUBR-RET), it will depend the
specifications of each instruction.

4

3

2

1

8

6

7

2

5

4

3

1

6

4

5

3

2

1

5

3

7

6

4

2

1